faustinoaq / vscode-lex-flex-yacc-bison

Syntax highlighting for Lex, Flex, Yacc and Bison in VSCode.

Lex Flex Yacc Bison

Syntax highlighting for Lex, Flex, Yacc and Bison.

This extension is based on these extensions:

1. Lex/Flex
2. Yacc/Bison

Overview

A compiler or interpreter for a programming language is often decomposed into two parts:

1. Read the source program and discover its structure.
2. Process this structure, e.g. to generate the target program.

Lex and Yacc can generate program fragments that solve the first task.

The task of discovering the source structure again is decomposed into subtasks:

1. Split the source file into tokens (Lex).
2. Find the hierarchical structure of the program (Yacc).

Read more in Lex & Yacc Page

Known Issues

Some keywords aren't detected.

Release Notes

See Change Log.

Contributing

1. Fork it https://github.com/faustinoaq/vscode-lex-flex-yacc-bison/fork
2. Create your feature branch git checkout -b my-new-feature
3. Commit your changes git commit -am 'Add some feature'
4. Push to the branch git push origin my-new-feature
5. Create a new Pull Request

Contributors

• @faustinoaq Faustino Aguilar - creator, maintainer

vscode-lex-flex-yacc-bison's Issues

add problemMatcher definitions for flex and bison

that would only be an adjustment to package.json; if I know this would be merged and a new release done, then I'd also do the necessary changes

Broken Syntax Highlight after '('

Using the extension I found a bug in the syntax highlight. It looks like it is broken after a ( character, see the screenshot:

Here is the plain code to copy and paste:

%option yylineno
%option nounput
%option noinput
%option nodefault

%{
#include "minako.h"
%}

%%
{whitespace}+ { /* nothing */ }

","           { return ','; } 
";"           { return ';'; } 
"("           { return '('; } 
")"           { return ')'; } 
"{"           { return '{'; } 
"}"           { return '}'; } 

<<EOF>>       { return EOF; }
%%

Unfortunately I was not able to fix the problem.

Does not support .lex extension

In my compilation course (and from what I see online) .lex extension is pretty common for lex files.
Should add support for this extension in a future update.

FR: please co-publish on Open VSX Registry

Please add this useful extension to the Open VSX Registry, which currently includes an outdated fork of this extension.

Details on the publishing can be found at https://github.com/eclipse/openvsx/wiki/Publishing-Extensions.

A bit of explanation:
Open VSX Registry is the default extension provider endpoint for several free builds of vscode like VSCodium and also gitpod and also for Eclipse Theia. It would be nice to have this extension directly be published to a free vsix repository, instead of only publishing it to the Microsoft Marketplace with its restrictions.

You could also use a GitHub action that allows publishing to Open VSX and the MS market place, HaaLeo/publish-vscode-extension does this.

Flex - Not recognising

Not highlighting correctly start condition scope as presented on flex manual here (pg. 25):

below program works fine:

Add extra lex file suffixes equivalent to the yacc suffixes

The extension currently recognises lex / flex suffixes ".l" and ".flex"
while for yacc / bison it recognises ".y", ".yy", ".ypp", ".yxx", ".y++" and ".bison" / ".BISON"

Consider extending the set of lex suffixes recognised similarly:

.l, .ll, .l++, .lxx, and .lpp

See, for example, autotools yacc & lex docs:

Similarly, lex source files can be used to generate C or C++; the extensions .l, .ll, .l++, .lxx, and .lpp are recognized.

Workaround: change language mode to flex / lex:
Ctrl-Shift-P -> "Change Language Mode" -> Flex/lex

[flex] Syntax highlighting breaks after escaped '

Syntax highlighting reacts to escaped ' as if the ' was not escaped.

Screenshot from VSCode default dark theme:

Can you make this plugin for vs2019

Now vs2019 does not have flex and bison highlighting plug-ins, is there any idea of porting this plug-in to vs2019

$$ is not highlighted

Some keywords like $$ is not highlighted when I open a bison file. And it is weird that some C code is highlighted normally and some isn't. Did I do something wrong?